how to recover backup file which is corrupted

I have a backup file(Full backup) which is Corrupted can you please recommand me how to recover the data from it. Few details are as below.
Size of the backup : 8GB.
How did i comform the bacup file is corrupt: When I am using to restore the backupfile either with EM or Quiery Analyzer it is giving that the backup file is not a valid MSBackup set and even when i tried to verify the backup with verify list only it is throwing an error not a vailed backup.